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What is used to remove permanent hardness of water?
Baking soda
Bleaching powder
Washing soda
Sodium Hydroxide
Washing soda
Washing soda (Sodium carbonate decahydrate, Na2тАЛCO3тАЛтЛЕ10H2тАЛO) is used to remove permanent hardness of water. It reacts with soluble calcium and magnesium chloride or sulfate salts in hard water to form insoluble carbonate precipitates.
Washing soda (Sodium carbonate decahydrate, Na2тАЛCO3тАЛтЛЕ10H2тАЛO) is used to remove permanent hardness of water. It reacts with soluble calcium and magnesium chloride or sulfate salts in hard water to form insoluble carbonate precipitates.
Adding washing soda to hard water is like adding a clarifying agent to muddy water that binds to the suspended dirt particles and causes them to settle down at the bottom so you can pour out clear water.
Remember: Washing away the permanent hardness with Washing Soda (Sodium carbonate).
CaCl2тАЛ+Na2тАЛCO3тАЛтЖТCaCO3тАЛтЖУ+2NaCl тАФ Removal of calcium hardness
MgSO4тАЛ+Na2тАЛCO3тАЛтЖТMgCO3тАЛтЖУ+Na2тАЛSO4тАЛ тАФ Removal of magnesium hardness
Permanent hardness is caused by the presence of dissolved chlorides and sulfates of calcium ([CaCl2тАЛ], [CaSO4тАЛ]) and magnesium ([MgCl2тАЛ], [MgSO4тАЛ]). When washing soda is added to hard water, it precipitates these calcium and magnesium ions as insoluble carbonates, which can then be easily filtered out.
CaCl2тАЛ+Na2тАЛCO3тАЛтЖТCaCO3тАЛтЖУ+2NaClMgSO4тАЛ+Na2тАЛCO3тАЛтЖТMgCO3тАЛтЖУ+Na2тАЛSO4тАЛ
Permanent hardness is caused by soluble chlorides and sulfates of calcium and magnesium.
It cannot be removed by simple boiling.
Washing soda (Sodium carbonate) converts these soluble salts into insoluble metal carbonates.
Ion-exchange resins (Permutit process) and synthetic resins are other major methods to remove permanent hardness.
Makes hard water soft and suitable for laundry and industrial boilers.
Prevents scale formation in heating equipment and pipes.
Requires careful dosing to avoid excess alkalinity in water.
Insoluble precipitates must be filtered out.
Domestic laundry and cleaning agents
Water treatment plants for municipal and industrial use
Option A (Baking soda, NaHCO3тАЛ) is used as an antacid and in baking, not for softening water.
Option B (Bleaching powder, CaOCl2тАЛ) is used for disinfection and bleaching.
Option D (Sodium hydroxide, NaOH) is a strong alkali used in soap making and chemical manufacturing.
C is correct тАФ Washing soda is used to remove